Table Saw Trouble

[Doug Pettway]

Hi all,

i bought a Delta contractors saw 36-979 a couple of months ago and i have had a hopefully simple problem that i am hoping one of you can help me with.

today i was lowering the blade (with the saw turned off) down below the table and, for lack of better terms, the motor dropped. not to the floor but beyond where it normally hangs. when it does this the whole motor and motor mount assembly kind of twists so that the belt is pressed hard up against the pulley guard.

the first time this happened i had thought that the belt wasnt tensioned enough so i moved the motor as far back on the mounting plate as i could to provide more tension. the saw ran fine until today. perhaps my theory was wrong. i cant move the motor any further back. do these belts stretch when they are new?

i am going to upgrade to the power twist link belt soon but for now i'd like to at least understand why this is happening.

thanks in advance

[Chuck Lenz]

Do you mean just one side of the motor drops ? As in the arbor side or the other end where the wireing comes out of the motor ? If so, it sounds like a pin on one side of the motor bracket is not seated in a motor plate hole fully. There should be a spring between those 2 pins preventing the pins from comeing out. Is this a new or used saw ? And have you looked at the owners manual in it's entirety ?

[Doug Pettway]

the pins are all the way in. both sides of the motor drops.

to try and describe it:

in normal operation: if you connect the two pulleys with an imaginary line the pivot point is below that line.

when the motor drops: the motor pulley actually falls far enough down that the pivot point is actually above that imaginary line.

wow, i hope that makes some kind of sense. i didnt have a camera with me to take a picture.

its a new saw and i read the manual several times. i'm going to call Delta tomorrow to see what they say.

[Chuck Lenz]

Well you've got me stumped on that one. I mean I think I understood what you just said, I'm just puzzled as what it could be causeing the problem. Did you try lubeing the raiseing mechanism ? Maybe thats dry and binding. When you figure it out I'd like to hear what it was.

[Brett Elliott]

I think a picture would be most helpful.

[Doug Pettway]

ok.i tried to draw up a depiction of whats going on. i have the motor mount disassembled at the moment.

i sent an email to Delta Support, we'll see what happens there.

[Pat Germain]

If I'm understanding you correctly, Doug, is it possible you've just got the motor adjusted too low? I know my contractor saw has a mounting plate with slots. The plate moves up and down and is held in place with bolts. I imagine if I adjusted the plate too low, the belt would hit something with the blade down low.

[Doug Pettway]

hmmm. there's a thought that i hadnt tried. i had it in my head that there wasnt enough tension so i was trying to move the motor back to increase the tension. perhaps, i was going the wrong way with it. i will have to give that a shot once i get back to the shop.

[Mike Null]

Does yours look like this?

[Doug Pettway]

yup, thats pretty close to mine.

[Mike Null]

As near as I can tell there's only one place that would allow for slippage and that's the base of the motor mount. Even there it can only move about an inch.

If your motor is mounted securely then I would have another look at the pins and the way you have them installed.

[Bill Huber]

Could it just be the belt is to long.

I know with my old Craftsman I put a to long of a belt on it and it would do something very close to what you are saying.

Got just a little shorter belt and it would fine.

[Cliff Rohrabacher]

a bolt prolly came loose.

[Doug Pettway]

thats what i was thinking at first. it will be a couple of days til i can go back to the shop and take a look at it. i spent most of yesterday fine-tuning my new bandsaw.

i really appreciate all the help that has come my way.



Could it just be the belt is to long.

I know with my old Craftsman I put a to long of a belt on it and it would do something very close to what you are saying.

Got just a little shorter belt and it would fine.

[joe greiner]

It looks like the line between the motor and the arbor is close to going over-center with respect to the motor mount, so that belt tension pulls the motor down instead of up. Same mechanism as vice-grips, toggle clamps, draw latches, and such. A shorter belt should correct it.

Joe

[Doug Pettway]

ok. i'm going to get a link belt this weekend i think. i should be able to try experimenting with the length with those right?

thanks again

[Fred Gulick]

from experience.... the plate that the motor is attached to is probably upside down check a picture in the manual against your set up. I was a LONG time finding it myself.

[Doug Pettway]

mine is upside down compared to the pics! argh!!!

now i remember looking at it when i was first unpacking it. the motor mount plate was already bolted onto the motor and it was upside down. i do remember that now. ok. i'll flip it over and if that solves the problem.

i feel like an idiot now.

[Fred Gulick]

I think with two of us doing it we can officially blame the manual! BTW get the link belt, the reduction in vibration is surprising, oh, and nice stealth gloat

[Doug Pettway]

haha. true, so true.

it wasnt meant to be a gloat. gloating would be me saying that i actually bought the TS, a 14" BS, 6" jointer, DW735 and a 26 gallon compressor at the same time. :)

but its my first real set of tools. i've been building guitars on an apartment balcony with a 9" BS and drill press for the past two years...and that's not fun.

[Doug Pettway]

thanks Fred, i owe you a beverage of your choice. i put the saw back together (the right way) and all seems right with the world again.

[Fred Gulick]

I have a lawn chair set up by mine so i can just sit and look at it when its not in use.